Best buy 300-350 watts
To pick out the best power supplies we divided them into two categories. The 300 and 350 watt PSUs for PCs using integrated graphics are at most a budget graphics card. The 400 and 450 watt PSUs for when you want to have a mid-range graphics card and perhaps even some overclocking headroom.
The 300 and 350 watt models are in the minority with 14 models. There are no modular PSUs here, and number we'd advise against buying due to very poor efficiency or ripple values.
The Seasonic G-Series 360W made the best impression in this category: a low ripple of 31.2 mVtt, 89% efficiency and only 31 dB(A) of noise. With an average price of 68 euros it's also the most expensive PSU in this segment. When we exclude all 50+ euro PSUs, we end up at the Seasonic S12II 380W. Introduced in 2008 already, it performs great on all fronts, and it even has sleeved cables.
The Be Quiet System Power 7 300W or 350W offer very good value for your money. Extremely silent, very good efficiency (85+ %) and a low ripple (less than 45 mVtt) and priced around 40 euros. Keep in mind that the 300W model doesn't have a PEG connector.
Seasonic G-Series 360W
Seasonic S12II 380W
Be Quiet! System Power 7 350W